Dispersion and cosmetic containing same

Abstract

A dispersion of fine inorganic particles comprising the following (a) to (c) components: (a) 10-70 mass % the inorganic fine particles, which are hydrophobized inorganic fine particles having a number-average primary-particle diameter, as determined by analyzing images on a transmission electron photomicrograph, of 10-200 nm;(b) 1.0-30 mass % aqueous component having one or more alcoholic hydroxyl groups; and(c) 1.0-20 mass % polyglycerin-modified silicone. The (c) component has dissolved in the (b) component. The dispersion has excellent dispersibility in aqueous media and high dispersion stability.

1 . A dispersion comprising components (a) to (c):
 (a) 10 to 70% by weight of a hydrophobized fine particle of inorganic powder having a number average primary particle diameter of 10 to 200 nm, as determined by image analysis of a transmission electron photomicrograph,   (b) 1.0 to 30% by weight of an aqueous component having at least one alcoholic hydroxy group, and   (c) 1.0 to 20% by weight of a polyglycerin-modified silicone which dissolves in component (b).   
     
     
         2 . The dispersion of  claim 1  wherein the fine particle of inorganic powder as component (a) has a UV-shielding effect. 
     
     
         3 . The dispersion of  claim 2  wherein the fine particle of inorganic powder as component (a) is titanium oxide. 
     
     
         4 . The dispersion of  claim 1  wherein component (a) is a fine particle of inorganic powder which has been hydrophobized with at least one agent selected from stearic acid, isostearic acid and triethoxycaprylylsilane. 
     
     
         5 . The dispersion of  claim 1  wherein component (b) is a compound having two alcoholic hydroxy groups in the molecule. 
     
     
         6 . The dispersion of  claim 1  wherein component (c) is polyglyceryl-3 disiloxane dimethicone. 
     
     
         7 . The dispersion of  claim 1  wherein the ratio of the amount of component (c) to the amount of component (b), (c)/(b), is from 0.35/1 to 1.0/1. 
     
     
         8 . The dispersion of  claim 1 , further comprising (d) water. 
     
     
         9 . The dispersion of  claim 8  wherein the content of component (d) is 8 to 82% by weight of the dispersion. 
     
     
         10 . A cosmetic composition comprising the dispersion of  claim 1 .